Background: The cafeteria diet (CAFD) model has been used to mimic the Western-style “junk food” eating pattern, inducing obesity in rodents. As the dietary composition varies across studies, we developed a CAFD model based on commonly consumed Brazilian ultra-processed foods to evaluate its effect on weight gain, metabolic parameters, and gene expression in C57BL/6 mice.
Methods: Forty male C57BL/6 mice were assigned to either a standard diet (SD) group or a CAFD group for 16 weeks. Biometric data, glycemic control, insulin resistance (IR), hepatic steatosis, and serum leptin and adiponectin levels were assessed. Expressions of 27 genes involved in adipocytokine signaling, inflammation, apoptosis, lipid, and glucose metabolism were analyzed using quantitative real-time polymerase chain reaction in visceral (VAT) and subcutaneous (SAT) adipose tissues, liver, and skeletal muscle.
Results: CAFD-fed mice exhibited significantly greater weight gain, hyperglycemia, elevated IR, and hepatic steatosis compared to SD controls. Circulating leptin and adiponectin levels increased in the CAFD group. Gene expression analysis revealed significant dysregulation in VAT (19 genes), SAT (6 genes), liver (11 genes), and muscle (4 genes) of the CAFD group, affecting pathways related to adipocytokine signaling, oxidative stress, inflammation, apoptosis, and lipid and glucose metabolism. Additionally, an increased Itgax-to-Llgl1 ratio in VAT of the CAFD mice indicated a phenotypic shift in macrophages from M2 to pro-inflammatory M1.
Conclusion: This CAFD model efficiently induces obesity, metabolic dysfunction, and tissue-specific alterations in gene expression in C57BL/6 mice, supporting its use as a relevant model for studying the molecular and inflammatory mechanisms underlying diet-induced obesity.
Background: Zucker diabetic fatty (ZDF) rats exhibit significant phenotypic variability despite genetic uniformity, yet a comprehensive characterization of these divergent phenotypes remains limited.
Methods: Male ZDF (fa/fa) rats (4 months, n = 22) and ZDF (fa/+) lean controls (n = 10) were maintained on standard chow for 6 months. Based on metabolic trajectory, ZDF (fa/fa) rats were stratified into three phenotypes: obese normoglycemic (O, n = 8), diabetic with cachexia (D, n = 8), and diabetic without cachexia (D-C, n = 6). Comprehensive assessments included body weight, glycemic control, hepatic function, oxidative stress markers, and inflammatory cytokines.
Results: Principal coordinate analysis confirmed significant metabolic separation between phenotypes (p < 0.01). Diabetic cachectic (D) rats exhibited severe hyperglycemia (>25 mmol/L), insulin depletion, elevated hepatic enzymes (alanine aminotransferase [ALT] increased 2.5-fold, p < 0.01), elevated interleukin-6, and delayed pain response. Diabetic rats without cachexia (D-C) exhibited intermediate hyperglycemia (≈13 mmol/L, p < 0.001 vs. control) with preserved insulin levels, and elevated fibroblast growth factor 21 (FGF21) and soluble receptor for advanced glycation end products (sRAGE). Obese normoglycemic (O) rats maintained normoglycemia with hyperinsulinemia and elevated triglycerides.
Conclusion: Under identical genetic and environmental conditions, ZDF (fa/fa) rats develop distinct metabolic phenotypes encompassing euglycemic obesity, pre-cachectic diabetes, and advanced cachectic diabetes. Phenotypic stratification is essential for accurate interpretation of ZDF experimental data and underscores the importance of characterizing individual metabolic trajectories when diabetic complications and therapeutic interventions are assessed in this model.
Childhood obesity is closely linked to the rising incidence of precocious puberty (PP), yet valid preclinical models of obesity-related PP remain lacking. High-fat diets (HFD) are widely used for obesity models, but the suitability of different HFD formulations for inducing PP is unknown. Female Sprague–Dawley (SD) rats were randomized to control, 45% HFD, or 60% HFD groups at postnatal day (PND) 21. Body weight and daily caloric intake were monitored; vaginal opening (VO) was recorded from PND 35. At study termination, serum levels of estradiol (E2), luteinizing hormone (LH), follicle-stimulating hormone (FSH), gonadotropin-releasing hormone (GnRH), leptin, and adiponectin were measured. Ovarian histology and vaginal cytology were assessed. In vitro, GT1-7 cells were treated with recombinant mouse leptin for 24 h, and GnRH secretion was quantified. Compared to controls and the 60% HFD group, rats fed 45% HFD exhibited significantly increased body weight, earlier VO onset, and elevated weights of organs. The 45% HFD group also had higher serum E2, LH, FSH, GnRH, and leptin levels, alongside reduced adiponectin; ovarian histology showed advanced follicular development, and vaginal smears displayed estrus-stage cytology. In contrast, the 60% HFD group had no significant changes in body weight or hormonal parameters, and limited ovarian development. In vitro, leptin treatment significantly upregulated GnRH secretion in GT1-7 cells. The 45% HFD formulation is optimal for constructing a juvenile rat model of obesity-related PP, as it recapitulates key phenotypic, histological, and endocrine features of the disease.
Dry eye disease (DED) is a prevalent and complex multifactorial ocular surface disorder, leading to significant visual discomfort and diminished quality of life. Animal models are indispensable tools for investigating DED pathology and evaluating therapeutic interventions. This review aims to systematically summarize the primary types of animal models of DED, detail their establishment methods and pathophysiological features, explore their value in elucidating key mechanisms, critically assess their strengths and limitations, and discuss their application prospects. A comprehensive literature search was conducted in electronic databases, including PubMed, Web of Science, and Google Scholar, with a primary focus on literature published within the past decade. Diverse animal models successfully replicate core features of different DED subtypes. Aqueous-deficient models (e.g., surgical excision, scopolamine) mimic tear volume reduction and lacrimal gland inflammation. Evaporative models (e.g., desiccating stress, benzalkonium chloride) effectively simulate tear film lipid layer dysfunction and increased evaporation. Neurogenic models reveal the critical role of neural regulation and neuroinflammation, whereas multifactorial models (e.g., autoimmune, environment-drug combinations) offer high clinical relevance by integrating multiple pathogenic factors. These models have been instrumental in identifying key inflammatory signaling pathways (e.g., NF-κB), immune cell infiltration dynamics, and corneal nerve morphological and functional changes. Animal models are crucial for advancing our understanding of DED pathogenesis and developing novel therapies. The rational selection and application of appropriate models, based on research objectives, are paramount for enhancing translational relevance. These efforts are essential for bridging the translational gap between preclinical research and clinical application.
Exosomes have emerged as promising therapeutic carriers, with over 40 000 scientific publications reflecting their exponential growth in biomedical research. Cardiovascular diseases (CVDs) are the leading cause of mortality worldwide. Among these, myocardial infarction (MI) represents the most prevalent and devastating form, contributing significantly to global morbidity and mortality. Reducing the mortality and long-term complications associated with MI is therefore both necessary and urgent. Exosomes, naturally occurring extracellular vesicles, offer a promising cell-free alternative for drug delivery and cardiac repair and regeneration after ischemic injury due to their ability to transport bioactive proteins, lipids, and RNA. This narrative review summarizes recent advancements in exosome-based therapeutics for ischemic heart disease, focusing on the efficacy of various animal models. Various approaches are being studied to optimize exosome-based therapies, including methods to enhance their stability, targeting ability, and bioavailability in the cardiovascular system, highlighting the potential of exosomes not only as drug delivery vehicles but also as regenerative mediators capable of promoting myocardial repair and reducing MI. With continued advances in exosome technology and a deeper understanding of their biological functions, there is growing optimism that these vesicles could pave the way for more effective and less invasive treatments for cardiovascular diseases in the near future.
Background: The incidence of C5 palsy after cervical surgery (C5P) was high (>5%), although its pathogenesis is still not clear. Although most patients (>95%) could have apparent enhancement, there are still some patients who cannot achieve satisfactory functional recovery, and it seriously affects their quality of life. At present, there is no appropriate animal model that could be used to research new interventions for permanent C5P.
Methods: Following anatomical validation confirming precise exposure of the C5 ventral root, we established a novel mouse C5P model using a posterior intradural approach to selectively transect the C5 ventral root while preserving the dorsal root and avoiding lateral/anterior cervical dissection. Multimodal validation (behavioral, electrophysiological, histological) confirmed selective motor deficits, denervation atrophy, and intact sensory pathways.
Results: The posterior approach for intradural C5 ventral nerve root injury offers sufficient operative space and is a safe surgical technique, ensuring the successful postoperative survival of all mice involved. By excising the C4 and C5 vertebral arches to facet joint and opening the spinal dura mater and arachnoid mater, the ventral root of C5 can be clearly exposed and severed, whereas the dorsal root can be well preserved. Behavioral and electrophysiological tests showed functional lesion, and histological assessments revealed pathological changes in muscle and nerve tissues.
Conclusions: This study describes a simple, reproducible, and effective mouse model of permanent C5P for exploring potential new therapies (such as nerve transfer surgery and other cutting-edge rehabilitations).
Background: Idiopathic pulmonary fibrosis (IPF) is an irreversible, fatal lung disease. Methylophiopogonanone A (MOA), derived from the Chinese medicinal herb Ophiopogon japonicus, has been shown to exhibit anti-inflammatory and antioxidant properties. However, the effects of MOA on pulmonary fibrosis remain unclear. This study aims to evaluate the antifibrotic effect of MOA.
Methods: The antifibrotic efficacy of MOA was evaluated in a bleomycin (BLM)-induced pulmonary fibrosis mouse model, using pirfenidone (PFD) as a positive control. Assessments included histopathology, micro-computed tomography (micro-CT), lung function tests, and serum biochemistry. In vitro, RAW 264.7 murine monocyte/macrophage cells were stimulated with BLM, lipopolysaccharide (LPS), interleukin 4 (IL-4), recombinant secreted phosphoprotein 1 (SPP1) protein, or Spp1 overexpression (OE-spp1) and treated with MOA, PFD, spp1 shRNA (sh-spp1), or the PI3K inhibitor LY294002. Transcriptomics, molecular docking, microscale thermophoresis (MST), immunohistochemistry, immunofluorescence, and Western blot were used for mechanistic exploration.
Results: MOA administration significantly attenuated BLM-induced lung fibrosis and collagen deposition, improved lung function, and did not induce hepatorenal toxicity. Integrated transcriptomic and bioinformatics analyses identified SPP1 as a key potential target. Molecular docking simulation and MST assays further confirmed a favorable binding affinity between SPP1 and MOA. MOA potently inhibited both M1 and M2 macrophage polarization in vivo and in vitro. Mechanistically, MOA attenuated BLM-induced pulmonary fibrosis by suppressing SPP1-mediated macrophage polarization via inhibition of the PI3K/Akt pathway.
Conclusions: This study identifies that MOA is a promising natural compound that alleviates pulmonary fibrosis by inhibiting SPP1-mediated macrophage polarization via the PI3K/Akt pathway.
Background: SEC16A is a pivotal protein that facilitates the transport of proteins from the endoplasmic reticulum to the Golgi apparatus. Utilizing the protein structure function database, a potentially pathogenic mutation site (NM_014866.1: c.4606C>G(p.L1536V)) was pinpointed within the conserved central core region of the human SEC16A protein, a component integral to the COPII complex assembly.
Methods: Leveraging information on human gene mutations and aligning human and mouse protein amino acid sequences, the Sec16aL1551V/L1551V mouse model was successfully developed using CRISPR/Cas9 technology.
Results: Two behavioral experiments, namely novel object recognition and cued fear conditioning, revealed that Sec16aL1551V/L1551V mice demonstrated a phenotype of neurological impairment, evidenced by diminished abilities in learning and memory. Furthermore, while undergoing tail suspension, the Sec16aL1551V/L1551V mice displayed a distinctive limb clasping behavior, a characteristic typically associated with mouse models of chronic neurodegenerative diseases.
Conclusion: The Sec16aL1551V/L1551V mouse model developed in this study providing a powerful tool for better understanding of the pathogenic mechanisms of Sec16a gene mutations in brain dysfunction diseases.
Background: To combat hepatocellular carcinoma (HCC) disease heterogeneity and growing mortality, there is an urgent need for targeted and personalized therapeutics. While syngeneic mouse models are commonly used for preclinical validation of these therapeutics, the lack of genetically characterized murine cell lines adds uncertainty to the study of drug-gene interactions in these models. We previously generated a novel murine cell line, A52, from a diethylnitrosamine (DEN)-induced adiponectin-knockout mouse model. Here, we present a comprehensive genomic and transcriptomic characterization of the A52 cell line.
Methods: A52 cells were grown in various culture medium compositions to investigate robustness to simple media. Whole-genome sequencing (WGS) and RNAseq were performed on A52 cells from both cell culture and syngeneic tumor tissue, as well as a reference cell line representing non-tumor cells, AML-12.
Results: A52 was found to show robust growth in all medium compositions. Substantial chromosomal instability was observed in A52, including trisomy 15 and notable amplifications of oncogenic loci such as Myc and Cd274 (PDL-1), alongside frequent small variants and structural rearrangements. Notably, the cell line harbors the common HCC driver Braf V584E mutation, and a novel Plk1 p.R364W variant predicted as a driver mutation. Transcriptomic profiling defined a distinct “A52 gene signature” enriched in EGFR-ERBB signaling and cell migration pathways. Integrative analyses demonstrated that the A52 gene signature aligns closely with a subset of human HCC lacking CTNNB1 mutations.
Conclusion: This study provides a critical genetic resource, facilitating more precise preclinical modeling and therapeutic validation in HCC.
Background: Mutations in and functional inactivation of the Gorab gene cause gerodermia osteodysplastica (GO), a disease featuring wrinkled skin and osteoporosis, but the underlying mechanisms of skin aging remain incompletely understood.
Methods: By crossing the Gorab conditional knockout mouse model (Gorabflox/flox) with Col1a2-cre/ERT tool mice, pregnant dams at embryonic day 16.5 (E16.5d) and 6-week-old offspring were induced with tamoxifen dissolved in a corn oil solution (3 mg/150 μL per mouse) to develop a dermal Gorab knockout mouse model. Then, aging phenotypes were analyzed, and mechanistic studies were performed.
Results: Conditional knockout of Gorab at two different time points (embryonic and postnatal) resulted in elevated levels of aging-related proteins (P53, P21, P16) and a reduction in levels of extracellular matrix (ECM) components, including collagen, fibrillin-1, vimentin, fibronectin, laminin, and versican in the ventral and dorsal skin of adult mice. Postnatal knockout had a relatively more pronounced effect on skin aging-related changes. Mechanistically, Gorab knockout impaired the ubiquitination and promoted the accumulation of P53 protein, likely through regulating the E3 ligase RCHY1. This was accompanied by increased HDAC2 levels, reduced histone acetylation, and consequent downregulation of skin ECM proteins, outlining a potential pathway for accelerated skin aging.
Conclusions: This study elucidates that Gorab mutations in the dermis promote skin aging by causing P53 accumulation and disrupting ECM expression via epigenetic regulation. These findings clarify the biological role of Gorab in skin aging and provide a theoretical basis for related mechanistic research and potential preventive strategies.
Background: Currently, there is no imaging-based method for directly detecting active diastolic dysfunction. This study aimed to evaluate the efficacy of isovolumic relaxation strain imaging (IVSI) in assessing active diastolic dysfunction in preclinical settings.
Methods: Active diastolic function was assessed in C57BL/6J mice subjected to transverse aortic constriction (TAC) or a sham operation using daily conventional echocardiography and strain imaging over a 14-day period, with follow-ups at weeks 4 and 8. A modified approach was developed to accurately identify the isovolumic relaxation time (IVRT) using an apical three-chamber view.
Results: The novel imaging protocol successfully identified IVRT in each mouse. TAC mice exhibited significant alterations in E/A and E/E′ ratios from day 12 to 14, while the average strain rate detected by IVSI showed a significant decrease from day 4. After 8 weeks, TAC mice developed severe heart failure with reduced ejection fraction, but conventional echocardiography failed to detect diastolic dysfunction.
Conclusion: IVSI continued to indicate obvious diastolic alterations. Together, these data suggested that IVSI is an effective imaging-based method for direct detection of active diastolic dysfunction with high accuracy and sensitivity.
Background: Research has demonstrated that excessive loading can induce intervertebral disc degeneration (IDD). However, existing animal models have inherent limitations, and there is still no reliable model to investigate the effects of excessive loading on IDD. This study aims to develop an in vitro model of simulated excessive loading.
Methods: A total of 24 twelve-week-old Sprague–Dawley rats with similar body weights were randomly divided into four groups. In the compression suture group, a 5-mm-wide tail skin was removed, and the defect was compressed sutured with 2–0 silk thread. In the sham surgery group, only a 5-mm-wide tail skin was removed without compression suturing. All animals underwent radiological, histological, and molecular analysis at 2, 6, and 10 weeks postoperatively.
Results: X-rays and magnetic resonance imaging showed that the height of the intervertebral disc (IVD) and the water content of the nucleus pulposus (NP) decreased in the compression suture group. The histological results showed that the tissue structure of IVDs was disordered, and the proteoglycan content was reduced in the compression group. Compression induced upregulation of MMP-3 and MMP-13 expression in NP cells, whereas the expression of collagen II and aggrecan was downregulated. Additionally, an increased inflammatory response and apoptosis level were detected in NP cells of the compression group.
Conclusion: We conclude that simulated excessive loading induces IDD in rats. This is a reliable and highly reproducible IDD model that will provide a foundation to investigate the effects of excessive loading on IDD.
Background: Diabetic retinopathy (DR) is the most significant manifestation of diabetic microangiopathy. The existing tree shrew model of DR has dysfunctional retinal short wave sensitivity (SWS) cones and retinal ganglion cells, but it remains unclear whether the retinal microvessels are also compromised. In this study, we established a tree shrew diabetes model to investigate the characteristics of retinal microvascular disease observed in early human DR.
Methods: A high-fat and high-sugar diet combined with streptozotocin was used to establish the tree shrew diabetes model. After 20 weeks of sustained high glucose levels, we measured the thickness of each retinal layer and the number of ghost pericyte cells and acellular capillaries, and examined the ultrastructural changes in the retina. We also performed RNA sequencing (RNA-seq) and evaluated the protein expression levels of vascular endothelial growth factor (VEGF) and Bcl-2-related X protein (Bax).
Results: The tree shrew model exhibited the characteristics of diabetes, including hyperglycemia, hyperlipidemia, and insulin resistance. The retinal nerve fiber layer and ganglion cell layer exhibited significant thinning (36% and 30%, respectively). Retinal capillaries exhibited ghost pericytes and acellular capillaries, whereas the retinal ultrastructure exhibited signs of damage. VEGF and Bax protein levels in the retina were significantly upregulated. RNA-seq revealed downregulation of phosphoserine aminotransferase 1 (PSAT1). Overexpression of PSAT1 in retinal microvascular endothelial cells restored their lumen formation ability and mobility in a high-glucose environment, and reduced the expression of VEGF.
Conclusion: Our results indicate that the tree shrew may be a suitable experimental animal model for studying the pathogenesis of early DR. Furthermore, PSAT1 may be a promising molecular target for DR treatment.
Background: Based on human Rheumatoid Arthritis (RA) criteria, this study established a macaque collagen-induced arthritis (CIA) model and a standardized non-human primate (NHP) standardized diagnostic framework. Integrating these tools, we characterized three disease stages (IIR, e-RA, a-RA) and key early biomarkers, thereby providing a robust platform for investigating RA pathogenesis research and conducting preclinical evaluation of humanized macromolecular drugs.
Methods: CIA was induced in macaques via through immunization with bovine type II collagen emulsified in complete Freund's adjuvant. Disease progression was monitored using multimodal imaging (MRI, CT, X-ray, and ultrasonography), enabling comprehensive assessment of joint edema, vascularity, bone erosion, and cardiopulmonary function.
Results: The disease progression in CIA macaques was categorized into three stages: IIR (days 14–34), e-RA (days 35–41), and a-RA (days 42–70). Notably, bone erosion progressed independently of the resolution of joint swelling resolution, with a trend toward aggravated severity during the post-swelling phase. Furthermore, cardiac assessments demonstrated that valvular damage primarily affected the tricuspid valve, with more pronounced impairment of right ventricular diastolic function. Additionally, observed pulmonary inflammation suggests potential lung involvement, though its progression throughout the disease course requires further investigation.
Conclusions: The progression of CIA in macaques can be divided into three stages: IIR (14–34 days), e-RA (35–41 days), and a-RA (42–70 days). For RA patients, bone erosion should be prioritized in clinical monitoring, and cardiac assessment should focus on the tricuspid valve and right ventricular diastolic function.
Over one billion people worldwide suffer from obesity, and the number is continually rising. This epidemic is partly caused by the modern lifestyle. Animal models, especially mouse models, are crucial to identifying the genetic components of complex disorders and exploring the potential applications of these genetic findings. The body weight of the animals used in research is often measured regularly to monitor their health. Only endpoint measurements, such as ultimate body weight, are frequently examined in quantitative trait locus (QTL) studies; time series data, including weekly or biweekly body weight, are usually disregarded. QTL mapping using biweekly body weight measurements may be particularly intriguing in examining body weight gain in obesity research and identifying more genes associated with obesity and related metabolic disorders. This study is focused on identifying quantitative trait loci (QTLs) underlying body weight changes by analyzing biweekly weight measurements in collaborative cross (CC) mice maintained on a high-fat diet for 12 weeks. QTL analysis, utilizing 525 mice from 55 CC lines (308 males and 217 females), revealed genome-wide significant QTLs on different chromosomes for body weight changes over 12 weeks. This study unveiled 62 body weight QTLs, among which 28 novel QTLs associated with defined traits were observed and found not reported previously. In addition, 34 more QTLs were fine-mapped, as the genomic interval positions of these had been previously identified. These findings highlight genomic regions that influence body weight in CC mice, underscoring the value of time series data in identifying novel genetic factors.
Biomedical research and preclinical testing in large animal models are essential for developing and evaluating new medical devices. This ovine study presents a stepwise implantation protocol and initial experiences with a wireless blood pressure implant sensor, enabling continuous telemetric monitoring in sheep. Adult female Jezersko-Solčava sheep underwent implantation of a wireless blood pressure sensor into the ascending aorta via the right carotid artery. The body of the device can was positioned subcutaneously in the lower neck region. After skin closure, a computed tomography scan was performed to verify sensor tip location. If malposition was detected, surgical revision was undertaken immediately. Wireless blood pressure monitoring was conducted over a 24 h period in a custom-designed sheep barn. Twelve adult female sheep successfully underwent the implantation procedure, with no major complications reported. Sensor catheter revision was required in three animals (25%). The mean duration of the procedure (from incision to skin closure) was 36 ± 10 min. During the 24 h monitoring period, the average systolic and diastolic blood pressures were 93 ± 6 and 65 ± 5 mmHg, respectively. Large animal models, particularly sheep, are indispensable in cardiovascular device research due to their anatomical and physiological similarities to humans. This study demonstrates a rapid, minimally invasive protocol for wireless blood pressure sensor implantation in sheep, offering a valuable platform for chronic telemetric monitoring in the development of cardiovascular medical devices.